三甘醇，结构式HO(CH₂CH₂O)₂CH₂CH₂OH。

无色几乎无臭吸湿性粘稠液体，可燃。与水和乙醇混溶，微溶于乙醚，几乎不溶于石油醚。毒性极低，未见中毒病例。

Triethylene glycol, TEG, or triglycol is a colorless odorless viscous liquid with molecular formula HOCH₂CH₂OCH₂CH₂OCH₂CH₂OH. It is used as a plasticizer for vinyl. It is also used in air sanitizer products, such as "Oust" or "Clean and Pure". When aerosolized it acts as a disinfectant. Glycols are also used as liquid desiccants for natural gas and in air conditioning systems. It is an additive for hydraulic fluids and brake fluids and is used as a base for "smoke machine" fluid in the entertainment industry.